Data structure and features

 

Key–Value Databases (Riak): Data Structure and Features

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1. Data Structure in Key–Value Databases

Basic Structure

Key–Value databases store data in the form:

Key  →  Value

• Key: Unique identifier

• Value: Actual data (string, JSON, binary object, etc.)

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Example

"user_101" → { name: "Rahul", age: 25, city: "Pune" }

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Data Structure in Riak

Riak stores data as objects.

Each Riak object consists of:

• Key – Unique ID

• Value – Data content

• Bucket – Logical group of keys

• Metadata – Information about the object

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Buckets in Riak

• Similar to a collection

• Groups related key–value pairs

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2. Features of Riak

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1. Simple Key–Value Model

• Easy to understand and use

• Fast read and write operations

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2. High Availability

• No master node

• Data replicated across multiple nodes

• System remains available even if a node fails

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3. Eventual Consistency

• Data may not be immediately consistent

• Consistency is achieved over time

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4. Horizontal Scalability

• Add or remove nodes without downtime

• Uses commodity hardware

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5. Fault Tolerance

• Automatic data recovery

• Handles node failures gracefully

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6. Distributed Architecture

• Peer-to-peer design

• Uses consistent hashing

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7. Flexible Data Storage

• Stores structured and unstructured data

• No fixed schema

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3. Advantages of Riak Data Structure

• Simple and fast data access

• Easy to scale

• Suitable for distributed systems

• High reliability

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4. Limitations

• Limited querying capabilities

• No joins or complex queries

• Not suitable for relational data

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5. Use Cases

• Session management

• User profile storage

• Shopping cart data

• Cache systems